refactor(task): extract billing and polling logic from controller to service layer

Restructure the task relay system for better separation of concerns:
- Extract task billing into service/task_billing.go with unified settlement flow
- Move task polling loop from controller to service/task_polling.go (supports Suno + video platforms)
- Split RelayTask into fetch/submit paths with dedicated retry logic (taskSubmitWithRetry)
- Add TaskDto, TaskResponse generics, and FetchReq to dto/task.go
- Add taskcommon/helpers.go for shared task adaptor utilities
- Remove controller/task_video.go (logic consolidated into service layer)
- Update all task adaptors (ali, doubao, gemini, hailuo, jimeng, kling, sora, suno, vertex, vidu)
- Simplify frontend task logs to use new TaskDto response format

relay/channel/task/doubao/adaptor.go

@@ -2,7 +2,6 @@ package doubao
 
 import (
 	"bytes"
-	"encoding/json"
 	"fmt"
 	"io"
 	"net/http"
@@ -14,6 +13,7 @@ import (
 	"github.com/QuantumNous/new-api/dto"
 	"github.com/QuantumNous/new-api/model"
 	"github.com/QuantumNous/new-api/relay/channel"
+	taskcommon "github.com/QuantumNous/new-api/relay/channel/task/taskcommon"
 	relaycommon "github.com/QuantumNous/new-api/relay/common"
 	"github.com/QuantumNous/new-api/service"
 
@@ -131,7 +131,7 @@ func (a *TaskAdaptor) BuildRequestBody(c *gin.Context, info *relaycommon.RelayIn
 		return nil, errors.Wrap(err, "convert request payload failed")
 	}
 	info.UpstreamModelName = body.Model
-	data, err := json.Marshal(body)
+	data, err := common.Marshal(body)
 	if err != nil {
 		return nil, err
 	}
@@ -154,7 +154,7 @@ func (a *TaskAdaptor) DoResponse(c *gin.Context, resp *http.Response, info *rela
 
 	// Parse Doubao response
 	var dResp responsePayload
-	if err := json.Unmarshal(responseBody, &dResp); err != nil {
+	if err := common.Unmarshal(responseBody, &dResp); err != nil {
 		taskErr = service.TaskErrorWrapper(errors.Wrapf(err, "body: %s", responseBody), "unmarshal_response_body_failed", http.StatusInternalServerError)
 		return
 	}
@@ -165,8 +165,8 @@ func (a *TaskAdaptor) DoResponse(c *gin.Context, resp *http.Response, info *rela
 	}
 
 	ov := dto.NewOpenAIVideo()
-	ov.ID = dResp.ID
-	ov.TaskID = dResp.ID
+	ov.ID = info.PublicTaskID
+	ov.TaskID = info.PublicTaskID
 	ov.CreatedAt = time.Now().Unix()
 	ov.Model = info.OriginModelName
 
@@ -234,12 +234,7 @@ func (a *TaskAdaptor) convertToRequestPayload(req *relaycommon.TaskSubmitReq) (*
 	}
 
 	metadata := req.Metadata
-	medaBytes, err := json.Marshal(metadata)
-	if err != nil {
-		return nil, errors.Wrap(err, "metadata marshal metadata failed")
-	}
-	err = json.Unmarshal(medaBytes, &r)
-	if err != nil {
+	if err := taskcommon.UnmarshalMetadata(metadata, &r); err != nil {
 		return nil, errors.Wrap(err, "unmarshal metadata failed")
 	}
 
@@ -248,7 +243,7 @@ func (a *TaskAdaptor) convertToRequestPayload(req *relaycommon.TaskSubmitReq) (*
 
 func (a *TaskAdaptor) ParseTaskResult(respBody []byte) (*relaycommon.TaskInfo, error) {
 	resTask := responseTask{}
-	if err := json.Unmarshal(respBody, &resTask); err != nil {
+	if err := common.Unmarshal(respBody, &resTask); err != nil {
 		return nil, errors.Wrap(err, "unmarshal task result failed")
 	}
 
@@ -286,7 +281,7 @@ func (a *TaskAdaptor) ParseTaskResult(respBody []byte) (*relaycommon.TaskInfo, e
 
 func (a *TaskAdaptor) ConvertToOpenAIVideo(originTask *model.Task) ([]byte, error) {
 	var dResp responseTask
-	if err := json.Unmarshal(originTask.Data, &dResp); err != nil {
+	if err := common.Unmarshal(originTask.Data, &dResp); err != nil {
 		return nil, errors.Wrap(err, "unmarshal doubao task data failed")
 	}
 
@@ -307,6 +302,5 @@ func (a *TaskAdaptor) ConvertToOpenAIVideo(originTask *model.Task) ([]byte, erro
 		}
 	}
 
-	jsonData, _ := common.Marshal(openAIVideo)
-	return jsonData, nil
+	return common.Marshal(openAIVideo)
 }